Metal-turning lathe



(No-Model.)

P; LOBBEN.

METAL TURNING LATHB.

110.421,181. Patented Feb, 11,1890.

UNITED STATES PATENT OFFICE.

FEDER LOBBEN, OF XVORCESTER, MASSACHUSETTS.

METAL-TURNING LATHE.

.SPECIFICATION forming part of Letters Patent No. 421,181, datedFebruary 1.1, 1890.

Application filed October 2l, 1886. Serial No. 216,880. (No model.) v

To all whom t may concern.

Be it known that I, FEDER LOBBEN, a citizen of the Kingdom of Norway andSweden, and a resident of lVorcester, in the county of Worcester andState of Massachusetts, have invented an improvement in Turning-Lathes,of which the following is a specification.

My invention relates to that portion of a lathe known as the feedingmechanismf and it consists in providing means for connecting thetool-carriage with a revolving lead-screw, whereby the construction ofthe feeding mechanism is simplified, and by which the cutting-tool inthe operation of screw-cutting may he withdrawn at each cut and movedback and again advanced to the work for a succeeding cut in truerelation to the screw-thread to be cut; also, in providing improvedmeans for connecting the leadscrew with the live-spindle, and, further,in providing means by which the feeding mechanism is connected ordisconnected from the operating parts of the lathe.

The drawings hereunto annexed represent a turning-lathe embodying myinvention, and in which- Figure l is a front View of the lathe. Fig. 2is a View of the mechanism by which the tool-carriage is connected withthe lead-screw and shown partly in sectional view. Fig. 3 is a View,partly in section, of the mechanism by which rotary motion is impartedto the lead-screw and Fig. a vis a sectional View of a portion of theleadscrew and a part of its connected operating mechanism.

Like letters refer to like parts in the several figures.

Referring to the drawings,A denotes the bed of the lathe; B, thetool-carriageg C, the live-spindle; D, the lead-screw journaled in thebearings a a upon the lathe-bed.

E is a cone-pulley, and F a pinion upon a shaft F', driven by thelive-spindle C in the manner usual in machines of this class.

H is a cone-pulley running loosely upon the iixed bearing h, formed bythe extension of the box a. y

To the bearing l), l attach a gear c, and running loosely on thelead-screw D is a gear d.

Turning upon a stud e, which is carried by the cone-pulley ll, are thepinions f and y. The pinion f is in gear with the gearwheel c, and tothe pinion f is attached the pinion f, in gear with the gear-wheel d. Asthe cone H is driven by a belt from the conepulley E the pinions f and fare carried around the fixed gear-wheel c, causing the two pinions f andf to make as many revolutions on the stud e at each revolution aroundthe fixed gear o as the number of teeth in the pinion f is contained inthe number of teeth in the fixed gear c, and at each revolution of thepinion fthe pinion f will impart a rotary motion to the gear d equal tothe excess in size of the pinion fover the pinion f. If

- the gear-wheel chave one hundred teeth and the pinion j' twenty-fiveteeth, it will make four revolutions in turning' once around the lfixedgear c, and if the pinion f have twentyjsix teeth it will turn thegear-wheel d one tooth at each revolution,or fourteeth at eachrevolution of the pinion faround the fixed gear-wheel c. I am thusenabled to imparta rapid motion to the cone-pulley H, rendering thedriving-belt much less liable to slip and allowing a quicker speed to begiven to the live-spindle with a very slow feeding motion l to thetool-carriage, which is frequently de-` sirable, especially in lathes tobe driven by foot-power.

Running loosely upon the leadf-screw D 1s a gear-wneel g, driven by thepinion F on i the shaft F through an intermediate gearwheel 71'carriedon a lever pivoted concentrically with the lead-screw D, as is common inscrewcutting lathes.

Sliding concentrically in a ohamberi in the l lead-screw D is a rod J,having pins j and 7c sliding in slots j and 7c in the lead-screw. Thepingl projects beyond the screw D, so as to engage either the slot'Z inthe gear d or the slot l in the gearg as the sliding rod J is moved tothe right or left, thereby connecting either one of the gear-wheels CZor g with the leadscrew. Then the pin j is midway between the two gearsd and g, its projecting ends enteran annular chamber Z2 in the hub ofthe gear CZ, allowing both of the gears d and g to run loosely on theleadscrew. The ends of the pin 7o enter a collar K, having a groove Kadapted to receive a fork K2, mounted upon a sliding rod L;

held in the bearings m m', attached tothe lf" lathe-bed. The rod L hashandles L', by which the rod is conveniently moved by the operator.

A collar L2 is adj ustably attached to the rod L in proper position tobe struck by the apron M of the tool-carriage when the cuttingtool haspassed across the work, thereby moving the pin j out of the slotZin thegear-wheel d and into the annular chamber Z2, stopping the motion of thelead-screw and rendering the action of the feeding mechanism automatic.When the gear d is connected with the lead-screw by the pin j, thegear-wheel g will run loosely upon the screw, and when the gear gisconnected for the purpose of cutting a screw the gear-wheel d will runloosely upon the lead-screw. Therefore the change can be madeimmediately from the ordinary feeding motion of the cutting-tool to thatemployed in screw-cutting, and vice Versa, by simply sliding the rodJ tothe -right or left without making any change in the driving mechanism,and the motion of the cutting-tool may also be stopped -with equalfacility by bringing the pin j into the annular chamber Z2. Thegear-wheel g is held in place by a nut g', which permits the gear to beexchanged for any of the change-gears usually furnished with the latheby which the speed of the lead-screw may be varied relatively to thespeed of the work.

If it is not desired to employ a speed-reducing mechanism, the pin j maybe used, or some equivalent clutching device, between the gear g and thegear d, or a belt-pulley instead of the gear d, to which rotary motionmay be given directly.

`Iournaled in a projection N on the apron M is a nut N', through whichthe lead-screw passes. The projection N is inclosed by the collars N2,by which the apron M and connected tool-carriage are moved along theways of the lathe by the action of the lead-screw D in the nut N'.

To the nut N', I attach a beveled pinion N3, in gear with a beveledgear-wheel N4, journaled in the apron M, by a spindle N5, to which isattached the balanced arm N6, with a handle P, having a sliding motionin the arm N6. A spiral spring p is applied to the sliding handle tohold it in the socket N7 of the arm N G, and with the end p' projectingfrom the arm NG'to enter the chamber q in the stud q', projecting fromthe apron M. The sliding handle P is provided with a pin r, which entersthe slot 7^' in the arm NG. Vhen the pin r is withdrawn from the slot7", the handle is partially turned to keep the pin from re-entering theslot and hold the end p flush with the under side of the arm NG in orderto allow the arm to be rotated wit-hout the end p' coming in contactwith the stud q'.

The ratio of the gear. Nl to the pinion N3 is made to correspond withthe pitch of the lead-screw. In the lathe illustrated in the drawingsthe gears are two to one, so a single revolution of the gear N4 willproduce two revolutions of the pinion N3, andthe pitch of the screw D istwo threads to the inch, so one revolution of the arm N6 and gear N4will revolve the pinion equal to a motion of one inch on the lead-screw.If the pitch of the screw were three threads to the inch, the gearsshould be in the ratio of one to three, and such a corresponding ratioshould be observed between the gears and the pitch of the screw as shallcause a single complete revolution of the gear N"L to move thelead-screw D a distance equal to the pitch of a single complete threador a multiple thereof.

To the bed of the lathe I attach by a setscrew the stop S, so it may beadjusted along the bed to correspond with the position of the work.

In cutting a screw the carriage is moved back until the apron is broughtagainst the stop S, placed in proper position. The arm N6 is turned inthe direction opposite to that which would be caused by the 'action ofthe screw on the nut N' until the handle P is made to coincide with thechamber in the stud q', when the handle is turned in its socket,allowing the pin 7' to enter the slot r' and the spiral spring p toforce the projecting end p' of the handle into the chamber q.

The handle is thus held in position while the tool is advanced to thework of cutting a screw-thread. At the end of the cut the tool iswithdrawn and the carriage B is moved back against the stopl S, and thehandle I), which had been withdrawn from the stud q' in order to movethe carriage back, is again brought to coincide with the stud g' bybeing lturned against the action of the screw D to counteract the actionof the screw and hold the carriage against the stop S, thus securing thesame relative position of the cutting-tool at the commencement of eachcut. The carriage in the process of turning may be moved along the bedof the lathe by turningv the arm N6 and rotating vthe nut N' on thescrew D, thereby avoiding the use of the rack and pinion commonly usedin turning-lathes of this class and greatly simplifying the con,-struction of this part of the feeding mechanlSlIl.

If desired, the driving-power maybe disconnected from the screw D andthe cuttingtool fed by hand by rotating' the nut N' onthe lead-screw.

It will be obvious that instead of a leadscrew, as described, afeed-shaft may be employed without a screw-thread, so far as relates tothat portion of my invention concerned in reducing the speed of thelead-screw or of connecting or disconnecting it from the driving-power.

I am aware that a cone-pulley employed to drive a feed-shaft has beenused, journaled on a ixed bearing and concentrically with thefeed-shaft. Such I do not claim, broadly.

I am also aware that lathes have been known in which the carriage hasbeen moved by a screw working in a rotatable nut journaled IOO IIO

in the carriageand provided With locking mechanism by Which the nut isheld from rotation and released at Will. Such I do not herein claim, assuch a construction was shown in the Letters Patent to Spencer, No.356,509, January 25, 1887, and to Lathan1,No. atlSS, June 22, 1886. y

In the lathe illustrated in the accompanying drawings the nut islockedby a pin carried by the crank-arm and forming the crankhandle,which is made to enter a chamber q in the outerface of the carriage,andby which the operator is enabled to judge of the position of the nutby means of the position of the handle P relative to the chamber q. Ialso employ in connection With the nut-locking device an adjustable stopattached to the bed or other rigid portion of the lathe, Which enablesthe longitudinal movement of the carriage in its reverse motion to bedetermined. It in the operation of screw-cutting the leadscreW D makesten complete revolutions, it is obvious that in order to reverse thecarriage and bring the tool in exactly the saine relation to the work bya reverse motion of the nut N ten revolutions it will be necessary tohold the Work and lead.-scre\v at absolute rest, Whereas by theemployment of the stop S, I turn the nut N bringing the carriage againstthe stop S and determining the longitudinal movement of the carriageupon the bed. The rotation of the screw D and corresponding rotation ofthe Work will bring the handle I) in position to enter the chamber q inthe carriage, thus insuring not only the position of the carriage on thebed, but also the proper position of the work to thecutting-tool. Thiscannot be accomplished without the use of the stop S or its equivalentin order to determine the position of the carriage, unless the screw Dis held at rest duringthe reverse motion of the carriage.

IVhat I claim, and desire to secure by lietters Patent, is-m l. Inaturning-lathe, the combinatiomwith a rotating eedshaft journaled inbearings on the bed of the lathe and suitably connected with thetool-carriage, of mechanism for rotating said feed-shaft, and consistiug of a pulley journaled on a fixed bearing concentric with thefeed-shaft, a gear-Wheel attached to the bearing of .said pulley, tWopinions of ditferent sizes and attached to each other and turning on astud carried bysaid pulley around said fixed gear, which is in mesh Withthe smaller of said pinions, and a gear concentric with said feed-shaftand capable ot' being connected therewith, said gear .being in mesh withthe larger of said pinions, as and for the purpose set forth. t

2. In a turning-lathe, the combination, with a feed-shaft provided witha screw-thread and suitably connected with the tool-carriage, of tWorevolving gears running loosely on said feed-shatt and connected withthe livespindle, substantially as described, and a sliding clutchingdevice by Which rotary motion is imparted to said feed-shaft, saidclutching 'device being placed between said revolving gears, so eitherof them may be connected or disconnected With said feedshaft, as and forthe purpose `set forth.

3. The combination, with the feed-shaft of a turning-lathe and arevolving Wheel running loosely on said shaft and driven by thelive-spindle, of a sliding rod held concentrically in said shaft andcarrying clutching devices, substantially as described, for engagingsaid revolving Wheel, and a sliding rod parallel with the feedshaft andsliding in bearings on the bed of the lathe, said sliding rod beingconnected With the rod held in the feed-shaft, so their motion Will besimultaneous, substantially as described.

4t. In a turning-lathe, the combination, with the feedeshaft and a gearrunning loosely on said shaft, driven by the livespindle, of a slidingrod held concentrically in said feedshaft and carrying clutchingdevices, substantially as described, Whereby the feedshaft is connectedor disconnected with said gear, a sliding rod held in bearings parallelwith said feed-shaft and connected with the rod held in the feed-shaft,and an adjustable stop on said parallel sliding rod, substantially asdescribed.

5. ln a turning-lathe, the combination, with a lead-scretv journaled inbearings on the bed of the lathe and a screwthreaded nut journaled in abearing on the toolcarriage and having collars inclosing said bearing,of a beveled pinion attached to said nut, a beveled gear held on aspindle journaled .in the tool-carriage, a crank-arm on said spindle,and a sliding' pin carried by said arm and arranged to engage a hole inthe toolcarriage, whereby the screwthreaded nut is held from turning inits bearing,substantially as described.

C. In a tlii1ii1iglatlie, the combination, With a leadscrew journaled inbearings on the bed of the lathe and a screwthreaded nut jour naled in abearing on the tool-carriage, of a cranlnarm j ournaled in thetool-carriage and connected With said nut, substantially as den scribed,a locking device whereby the crank.- arni is held in a fixed position,substantially as described, and an adjustable stop attached to the rigidportion of the lathe, whereby the longitudinal reverse movement of thecarriage is determined, said screw-threaded nut and said crank-arm beingso connected that the rotation of the cranlearm shall have a ratio totherotation of the nut corresponding to the pitch of the leacbscrew',substantially as described.

FEDER LOBBEN. Witnesses:

RUFUs Bi FOWLER, lynn J oHNsoN.

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